

#ifndef __FAST_A_TO_F_H_INCLUDED__
#define __FAST_A_TO_F_H_INCLUDED__

#include <stdlib.h>
#include <math.h>

namespace irr
{
    namespace core
    {

        const float fast_atof_table[] =	{
            0.f,
            0.1f,
            0.01f,
            0.001f,
            0.0001f,
            0.00001f,
            0.000001f,
            0.0000001f,
            0.00000001f,
            0.000000001f,
            0.0000000001f,
            0.00000000001f,
            0.000000000001f,
            0.0000000000001f,
            0.00000000000001f,
            0.000000000000001f
        };

        //! Provides a fast function for converting a string into a float,
        //! about 6 times faster than atof in win32.
        // If you find any bugs, please send them to me, niko (at) irrlicht3d.org.
        inline char* fast_atof_move(char* c, float& out)
        {
            bool inv = false;
            char *t;
            float f;

            if (*c=='-')
            {
                c++;
                inv = true;
            }

            f = (float)strtol(c, &t, 10);

            c = t;

            if (*c == '.')
            {
                c++;

                float pl = (float)strtol(c, &t, 10);
                pl *= fast_atof_table[t-c];

                f += pl;

                c = t;

                if (*c == 'e')
                {
                    ++c;
                    float exp = (float)strtol(c, &t, 10);
                    f *= (float)pow(10.0f, exp);
                    c = t;
                }
            }

            if (inv)
                f *= -1.0f;

            out = f;
            return c;
        }

        //! Provides a fast function for converting a string into a float,
        //! about 6 times faster than atof in win32.
        // If you find any bugs, please send them to me, niko (at) irrlicht3d.org.
        inline const char* fast_atof_move_const(const char* c, float& out)
        {
            bool inv = false;
            char *t;
            float f;

            if (*c=='-')
            {
                c++;
                inv = true;
            }

            f = (float)strtol(c, &t, 10);

            c = t;

            if (*c == '.')
            {
                c++;

                float pl = (float)strtol(c, &t, 10);
                pl *= fast_atof_table[t-c];

                f += pl;

                c = t;

                if (*c == 'e') 
                { 
                    ++c; 
                    f32 exp = (f32)strtol(c, &t, 10); 
                    f *= (f32)powf(10.0f, exp); 
                    c = t; 
                }
            }

            if (inv)
                f *= -1.0f;

            out = f;
            return c;
        }


        inline float fast_atof(const char* c)
        {
            float ret;
            fast_atof_move_const(c, ret);
            return ret;
        }

    } // end namespace core
}// end namespace irr

#endif

